In that column, I predicted that not only would the iPod be a hit (despite criticism that it was way too expensive among other things), but that the iPod’s descendants would replace the PC. This seemed fairly insane at the time — just a week after Apple had announced the iPod, before the world had fallen in love with digital music, and way before the iPhone would usher in the current era of connected devices.

There’s one part I thought I got wrong, in the intervening years — that hardware peripherals would enable these iPod descendants to replace computers. Instead, I thought, it ended up being software, in the form of apps both on the phone and in the cloud.

Now I think I was right all along, and that hardware peripherals will indeed play a big role in how the iPod descendants known as smartphones will replace computers.

In terms of digital audio, Audiobus provides a particularly good example of how “smart” portable devices are becoming more like computers — in that case, by being able to route musical signals from one app to another, the same way people have done for years on PCs.

Here are some points in favor of smartphones becoming the center of our digital lives — in a hardware sense:

1. AirPlay (and the Wannabes)

Apple is winning the race to connect smartphones to living room devices like televisions, stereo systems, and speakers — and it’s doing so via AirPlay. In fact, I think this may have been what Steve Jobs was talking about when he said he had “finally cracked” the code for uniting smart devices with the television.

Now, Microsoft and Google are finally waking up and trying to employ similar strategies (tailored to the strengths of each) for piping tunes, videos, and other stuff into rooms that don’t have traditional computers.

I wrote this story in a bar on an iPad that had a keyboard as its stand. That keyboard stand works with the iPhone too. You don’t need to sacrifice a full-fledged keyboard when the PC goes away. Yes, I know, this point is obvious, but it belongs on this list.

3. Moore’s Law

Stuff like this is a joke. Nobody uses it:

But it won’t be a laughing matter for too much longer. As you know, Moore’s Law dictates that processor speed doubles every 18-24 months. That trend applies to smartphones, mo(o)re or less. Already, early iPhone models cannot run many of today’s apps, in part because they’re too slow.

Not only that, but smartphone manufacturers face a big marketing issue: It’s not easy to market a glowing rectangular touchscreen without some other sort of differentiation. What, are they supposed to put a third camera on there? A fourth? Make it a triangle?

By delivering faster performance and more storage capacity, Apple, Samsung, and the rest can keep us all in upgrade cycles — and themselves in business. And as this happens, the difference in speed between a smartphone and today’s PCs will be indistinguishable, and then the smartphone will inevitably become faster.

At that point, the idea of docking a smartphone into a desktop, laptop, or even tablet won’t seem so ridiculous, and it will already have all your passwords, apps, bookmarks, preferences, and so on — and probably, as I wrote 11-plus years ago, some security measures, like biometrics.

4. The PAN Is Here

Let’s play buzzword bingo. Do you remember the Personal Area Network? For a while there after the turn of the millennium, people were talking about PANs, which are sort of like LANs, except instead of connecting devices to each other in a home or office, they would connect various devices on a person’s person.

Bluetooth headsets, the Nike+ iPod Sensor, and portable cellular hotspots are early examples of PAN entering the mainstream.

Now comes word (from Bloomberg) that Apple has about a hundred designers iWatch. Meanwhile, Google Project Glass runs Android, but probably won’t have modems on them. Would you really want a 5G modem pressed up against your brain all day? How do you think these and other newfangled things are going to connect to the internet? Most likely through a smartphone.

How are you going to update their firmware? Maybe in the beginning with a PC, but eventually, OTA (over the air) via the smartphone modem. How will they talk to other apps, and how will you adjust their controls and preferences? Smart money says it’s the smartphone.

5. Hardware Peripherals Can Power, Charge Smartphones

Moore’s Law, mentioned above, notoriously does not apply to battery life. When you push a Lithium Ion battery too hard, planes can catch fire, as can laptops and, ostensibly, smartphones.

Once we start docking smartphones into computer shells, speaker docks, car cradles (more on those below), and other peripherals, the opportunity exists to give the phone’s battery a boost, either from AC power or from the peripheral’s own Lithium Ion battery.

It’s easy to make fun of internet refrigerators… but if all it takes to make your refrigerator generate a shopping list is that you’ve docked your phone there to charge it, wouldn’t you look at that list at the grocery store? Of course you would.

6. The Cloud Needs Connections

This is what happens when Generation Z encounters a mouse.

When Pandora drove me around Las Vegas to see its early integration with the car at CES 2011, I asked CEO Tim Westergren whether he thought cars would have modems pretty soon. He said no.

His reasoning: People already have a modem in their pockets: their smartphones. In a sense, you might think of a smartphone as an internet connection with a touchscreen. Everything mentioned here — your PAN, television, stereo, speakers, refrigerator, car, and so on — might occasionally need an internet connection, and that internet connection is on your phone.